This invention relates to improvements in an elevator operating system.
Elevator operating systems have the function of responding to the detection of an abnormality occurring in the operation of the elevator car to automatically take an emergency expedient. For example, after a command door-opening signal has been issued, the door of the elevator car is normally opened within a time interval of from two to three seconds. At that time, even though, for example, eight second has elapsed, the door may not open beyond a predetermined width. This is determined to be a door opening disablement and the elevator car is caused to automatically travel to the next succeeding floor whereby a passenger or passengers is or are prevented from being confined in the elevator car. Then, when the door opening disablement is again detected, even at the next succeeding floor, the elevator car is put out of service, which is signaled to the operator by the illumination of a fault lamp. Then, the passenger or passengers confined in the elevator car is or are to be urgently rescued from the elevator car.
However, where the door has been able to open at the next succeeding floor, the elevator car is not put out of service and calls continue to be effected in normal service. Thus, at that floor where the door opening has been determined to be disabled, the elevator car may again repeat a similar abnormal operation with a high possibility that, each time the abnormal operation is performed, the passenger or passengers become uneasy and alternatively, a deterioration of service is caused.
Also, the door may open at the end of six seconds after a command door opening signal has been issued. Although such a door opening operation is clearly different from the normal door opening operation, any countermeasure may not be taken without detecting the door opening disablement. This causes a high possibility of repeating the similar abnormal operation resulting in the occurrence of objections that time is spent until the door opens, thereby causing the passenger or the passengers to be irritable or uneasy.
In addition, the abnormal operations of the elevator car involve the departure disablement, the door closing disablement, etc. The term "departure disablement" means that the elevator car does not depart after the lapse of a specified time interval reckoned from the issuance of a command departure and the term "door closing disablement" means that a car door can not be closed after the lapse of a specified time interval reckoned from the issuance of a command floor closing signal. Those abnormal operations cause objections similar to those resulting from the door opening disablement.
In order to eliminate the latter objections, there have been already proposed the following countermeasures
(a) Upon the occurrence of not less than a specified number of abnormal elevator operations within a predetermined time interval, which operations are returned back to the normal elevator operation before an automatic energency operation is performed, elevator car is put out of the service so as to not be responsive to calls occurring after that time.
(b) Upon detecting an abormal elevator operation at a floor, the response to calls for that floor is limited.
However, abnormalities of the operation of the elevator car may include temporary abnormalities resulting from passenger mischief, a floor doorsill getting clogged by dirt and so on. Upon detecting such a temporary abnormality, calls are permitted to be returned back to the normal service only after the operator or the like has inspected the temporary abnormality and removed its cause. This results in new objections that service to passengers is correspondingly deteriorated and the operator or the like is forced to spend his or her labor.
Accordingly, it is an object of the present invention to provide a new and improved elevator operating system arranged to be automatically returned back to the normal operation after the detection of an abnormality of the elevator operation when the detected abnormality is determined to have resulted from a temporary cause.